Commercial air filter



Dc. 19, 1933. G. WALLACE COMMERCIAL` AIR FILTER Filed Aug. 8, 1931 J/wf/Y T072. 60mm Mu/fc5. By.

NTM/vn.

Patented Dec.` 19, 1933 UNITED STATES PATENT oFFlcE 1 Claim.

of liquid at substantially right angles 'thereto and is subsequently passed thru a .filtering material prior to the entrance of said air into the motor.

Other objects, advantages, and features of in-` vention may appear from the accompanying drawing, the subjoined detailed description, and the appended claim.` f

In the drawing Y Figure' 1 is a transverse, sectional View of my lter. n Figure 2 is a sectional View taken at right angles to the position shown in Figure 1. v Figure 3 is a transverse, sectional view of the filter pack. Y

Referring more particularly to the drawing, the numeral 1 indicates a case closed at the top by a wall 2. A pan 3 iits over the bottom of the case 1 `and is limited in its upward movement by a bead 4 formed on the case. The pan is held in position on the case by means of a pair of bails 5 5 which are hingedly secured at their upper ends to ears 6-6 secured to the case. A strap 7 is secured to the bottom of the pan 3,

and the ends of this strap are bifurcated so as to receive the bails 5 5. A thumb nut 8 screws on to the bottom of each of the bails against the strap, thus holding the pan in position.

The pan is partially lled with oilV or some other suitable liquid shown at 9, and the purpose of this oil is to collect the sand and dirt which is present in the air. An intake pipe 10 is centrally positioned in the case 1 and extends downwardly into the case through the top wall 2. The lower end of this pipe is crimped so as to constrict the lower end as shown at 1l. The pipe 10 terminates either slightly above the liquid level or extends some what into the liquid. The purposecf the Vconstricted lower end of the pipe is to increase the velocity of the air which passes therethru. The air striking into the liquid causesafroth to be formed, which more effectively vcollects the dirt and sand. An

(Cl. 18S-10) outlet pipe 12 extends from the case 1 adjacent the upper end thereof to the air intake of the engine. v

To prevent the liquid from being drawn over into the engine, and aiso to further insure that all of the dirt will be removed from the air, I provide a ilter pack 13 which comprises an outer ring 14 and a central sleeve 15. The sleeve l5 ts over the pipe 10 as shown in Figures V1 and 2. Screen rings 16--17 extend between the sleeve 15` and the ring 14 and at the top and bottom respectively of said ring.

A fibrous packing 18, such as hail', steel wool, any other suitable material, is packed between the sleeve 15 and the ring 14. The air after impinging upon the `liquid body, passes upwardly thru the filtering material and `thence into the outlet pipe 12 to the engine.

A back iire relief valve 19 is provided in the top wall 2, and the valve is mounted on a stem 20 which is guided in a spider 21. The pressure causedby back firing of the engine will cause the Valve to lift and the pressure will be relieved in the upper part of thecase 1 instead of being transmitted downwardly to act upon the liquid 9. Y

The lter pack 13 is held in position by means of a spring ring 22 which ts into the bead 4 and this ring holds the lter pack against slipping downwardly. The pack is held against upward movement by butting against the inwardly extending bead 23. Y

Y Having described my invention, I claim:

An air filter comprising a case, a pan fitting `over the bottom of said case, a pair of bales attached tothe case, means on the pan engageable by the bales whereby said pan is removably held in positicn, a central, vertically extending intake pipe in case, the lower end of said pipe being ccnstricted, an outlet pipe adjacent upper end of eaidrcase, a iilter pack within the case surrounding said intake pipe, said lter pack comprising an outer metal ring, a central sleeve closely fitting the intake pipe, said central sleeve projecting below the bottoinsuriace of the lter pack whereby a hand hold is provided, a wire retaining screen at the top and bottom of the filter pack, a filter material between the wire screens, case having a groove therein below the filter pack and a split ring in said groove bearing against the lter pack whereby said filter pack is held in position.

GORDON WALLACE. 

